textproduct: Albany

SYNOPSIS

Bitter cold temperatures continues today with dry conditions. Two clipper systems move through eastern New York and western New England for tonight and Wednesday. The first one brings light snowfall north and west of Albany. The second system for Wednesday brings widespread snow during the morning hours. Then snow mixes with rain before transitioning to all rain for valley locations while higher terrain locations continue to see snow. Behind the clipper system, lake effect and upslope snow showers continue through the end of the work week.

SHORT TERM /THROUGH THURSDAY NIGHT/

Key Messages:

- Winter Storm Watches continue for the western Adirondacks and portions of the Mohawk Valley from 4AM Wednesday through 7AM Thursday.

- Winter Weather Advisories will likely be needed for portions of the southern Greens, eastern Catskills, and the Upper Hudson Valley on Wednesday as these locations could see greater than 4 inches of snowfall.

Discussion:

Surface high pressure today continues to move eastward bringing one more day of dry conditions across eastern New York and western New England. Bitterly cold temperatures continue today with highs in the teens and 20s. A weak passing clipper system brings light snowfall to locations north and west of Albany this evening into the early overnight hours tonight. As this is a fast and weak moving system, we're forecasting snowfall amounts to be between a trace and 2 inches(in the western Adirondacks). Between midnight and 3 AM we could see a brief lull in the precipitation as our next clipper system arrives from the Great Lakes region.

This system brings onset precipitation type to be all snow as colder air at the surface continues to contribute temperatures being below freezing. The current forecast supports temperatures across the western Adirondacks, southern Greens, and portions of the eastern Catskills to remain below freezing for an all snow event. Temperatures across valley locations will need to be monitored closely as snow mixes with rain before transitioning to all rain for the late afternoon hours. Outside of high terrain locations, the current forecast supports light rain/snowfall amounts. Snowfall amounts range between a coating to 2 inches. Rainfall amounts range between a tenth to a quarter. For southern Vermont, snowfall amounts in the valleys range between 1 to 4 inches with the higher terrain locations currently forecasted for 5 to 7 inches. For the eastern Catskills, most locations range between 2 to 5 inches with a few isolated locations in western Ulster county between 5 to 7 inches. These locations are in the highest terrain with elevations above 2500 feet.

For the western Adirondacks, latest NBM and high resolution model guidances continue to support the highest snowfall totals north of the Thruway (I-90) and south of NY-28. This narrow band of higher totals comes from where moderate to heavy bands of snowfall could set up for Wednesday. High resolution model guidances continue to fluctuate on if these bands move further north so snowfall totals continue to fluctuate between warning and advisory criteria which is why we continue to have the winter storm watch in effect for these locations. For the Mohawk Valley, temperatures rise above freezing during the afternoon hours for that transition over from snow to rain. Snowfall totals range on the lower end between 1 to 3 inches. Bottom line up front, the terrain and temperatures are going to be the biggest influence with this clipper system for snowfall totals. Be prepared for winter weather impacts on Wednesday afternoon and evening. By Wednesday night and Thursday morning, the clipper system heads north and east. Behind this system, lake effect snow showers and upslope snow return for Thursday as well as gusty winds.

Latest probabilities from the National Blend of Models (NBM) data for winds greater than 40 mph is between 30 and 70 percent for the Berkshires. Elsewhere across eastern New York and western New England are less than 30 percent. The higher side of those probabilities are for the eastern slopes as the terrain will play a part in if winds exceed 40 mph. Nevertheless, winds will be gusty Thursday afternoon as the surface low pressure system heads further north and east with winds gusting between 25 and 35 mph.

LONG TERM /FRIDAY THROUGH MONDAY/

Key Message:

- High confidence in below normal temperatures continuing, along with chances for light snow or snow showers.

Discussion:

Weak surface ridging looks to be over the area on Fri bringing mainly dry conditions, although with a westerly flow aloft some light lake effect snow showers may occur in parts of the W. Adirondacks and W. Mohawk Valley. It will remain chilly. A disturbance aloft brings additional chances for snow showers Fri night into Sat, with the highest probs west of the Hudson Valley due to lake effect/upslope enhancement. Any snowfall looks to be light at this time.

As an upper level low and large scale trough digs across the Great Lakes and SE Canada, the pattern becomes more amplified which could result in a brief window for cyclogenesis along/near the mid Atlantic coast Sat night into Sun. At this time guidance is showing potential for development, but also for a fairly weak/progressive system. This could spread some light snow into at least parts of the area. Will continue to monitor trends.

The upper trough settles into the Northeast Sun into Mon, with another Arctic air mass building in. So temperatures should be well below normal again during this time. 850 mb temperature anomalies from the NAEFS are forecast to be -1 to -2 STDEV. There will be some wind at least through Sun night with high pressure to the west, so wind chills could be below zero across much of the area. High pressure builds in on Mon with winds diminishing, but temperatures remaining cold.

AVIATION /11Z TUESDAY THROUGH SATURDAY/

Through 12z Wednesday...VFR conditions are expected to generally prevail through the 24 hour TAF period, with the only exception a small chance for brief -SHSN with MVFR vsby at KALB/KGFL/KPSF after 00z Wed. Will mention PROB30 at these sites. Otherwise, SCT high level clouds initially with increasing mid level clouds expected later this afternoon well ahead of a clipper system approaching from the Great Lakes. Winds will be calm into this morning, becoming southerly around 5-10 kt later this morning into this afternoon.

Outlook...

Wednesday Night: Moderate Operational Impact. Chance of RA. Thursday: Low Operational Impact. Breezy. Slight Chance of SN. Thursday Night: Low Operational Impact. Slight Chance of SN. Friday: No Operational Impact. NO SIG WX. Friday Night: Moderate Operational Impact. Chance of SN. Saturday: Moderate Operational Impact. Chance of SN.

ALY WATCHES/WARNINGS/ADVISORIES

CT...None. NY...Winter Storm Watch from late tonight through Thursday morning for NYZ032-033-038-082. MA...None. VT...None.